In Major League Baseball (MLB), an unassisted triple play happens when a defensive player makes all three outs in one continuous play without any assistance from his teammates. For this rare play to even happen, there must be no outs and at least two runners on base.

In MLB, a total of fifteen players have turned an unassisted triple play, making this feat rarer than a perfect game (23 perfectos as of October 2017). On July 19, 1909, Neal Ball, playing shortstop for the Cleveland Naps (now known as the Cleveland Indians) in the second inning of a game against the Boston Red Sox, caught a line drive, stepped on second base to retire the runner and tagged the runner that was on first base as he was advancing towards second. Because the play was so unprecedented and turned so smoothly, none of the other players on the field knew the inning was over. Starting pitcher Cy Young even asked Ball why he was leaving the field. When the fans realized what happened, Ball returned to the dugout to a standing ovation and hugs from his fellow teammates.

Cornelius 'Neal' Ball (April 22, 1881 – October 15, 1957) was an American baseball shortstop who played seven seasons in Major League Baseball (MLB). He played for the New York Highlanders (now known as the New York Yankees), Cleveland Naps and the Boston Red Sox from 1907 to 1913. Although his primary position was shortstop, Ball played at second base, third base and in the outfield as well.

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